Index: src/newgrf.cpp
===================================================================
--- src/newgrf.cpp	(revision 19055)
+++ src/newgrf.cpp	(working copy)
@@ -2325,6 +2325,8 @@
 									grfmsg(2, "IndustriesChangeInfo: Attempt to use industry tile %u with industry id %u, not yet defined. Ignoring.", local_tile_id, indid);
 								} else {
 									/* Declared as been valid, can be used */
+									itt[k].ti.x = (int8)GB(itt[k].ti.x, 0, 8);
+									itt[k].ti.y = (int8)GB(itt[k].ti.y, 0, 8);
 									itt[k].gfx = tempid;
 									size = k + 1;
 									copy_from = itt;
Index: src/industrytype.h
===================================================================
--- src/industrytype.h	(revision 19055)
+++ src/industrytype.h	(working copy)
@@ -84,6 +84,7 @@
 enum IndustryTileSpecialFlags {
 	INDTILE_SPECIAL_NONE                  = 0,
 	INDTILE_SPECIAL_NEXTFRAME_RANDOMBITS  = 1 << 0, ///< Callback 0x26 needs random bits
+	INDTILE_SPECIAL_DONT_BUILD            = 1 << 1, ///< Tile is not actually built (intended for checking clearance on layouts)
 };
 DECLARE_ENUM_AS_BIT_SET(IndustryTileSpecialFlags);
 
Index: src/industry_cmd.cpp
===================================================================
--- src/industry_cmd.cpp	(revision 19055)
+++ src/industry_cmd.cpp	(working copy)
@@ -1598,8 +1598,11 @@
 
 	do {
 		TileIndex cur_tile = tile + ToTileIndexDiff(it->ti);
-
-		if (it->gfx != GFX_WATERTILE_SPECIALCHECK) {
+		/* it->gfx is stored in the map. But the translated ID cur_gfx is the interesting one */
+		IndustryGfx cur_gfx = GetTranslatedIndustryTileID(it->gfx);
+		const IndustryTileSpec *its = GetIndustryTileSpec(cur_gfx);
+		
+		if (it->gfx != GFX_WATERTILE_SPECIALCHECK  && !(its->special_flags & INDTILE_SPECIAL_DONT_BUILD) && (it->ti.x >= 0) && (it->ti.y >= 0)) {
 			i->location.Add(cur_tile);
 
 			WaterClass wc = (IsWaterTile(cur_tile) ? GetWaterClass(cur_tile) : WATER_CLASS_INVALID);
@@ -1613,9 +1616,6 @@
 				SetIndustryConstructionStage(cur_tile, 2);
 			}
 
-			/* it->gfx is stored in the map. But the translated ID cur_gfx is the interesting one */
-			IndustryGfx cur_gfx = GetTranslatedIndustryTileID(it->gfx);
-			const IndustryTileSpec *its = GetIndustryTileSpec(cur_gfx);
 			if (its->animation_info != 0xFFFF) AddAnimatedTile(cur_tile);
 		}
 	} while ((++it)->ti.x != -0x80);